MD4 Hash Generator
Generate 128-bit MD4 message digests instantly
MD4 (Message-Digest Algorithm 4) was designed by Ronald Rivest in 1990 as a fast cryptographic hash function. It produces a 128-bit (32-character hex) hash value. While MD4 is now considered cryptographically broken and should not be used for security, it remains historically significant as the direct predecessor to both MD5 and the SHA family of algorithms. It's still actively used in Microsoft's NTLM authentication protocol.
What is MD4?
MD4 processes input in 512-bit blocks and produces a 128-bit hash through three rounds of operations. Each round uses a different nonlinear function. Rivest optimized MD4 for speed on 32-bit processors, making it one of the fastest hash functions of its era. MD5 was later created as a more secure replacement after weaknesses were found in MD4.
✅ MD4 Characteristics
- • Very Fast: Designed for maximum speed on 32-bit processors
- • 128-bit Output: Produces a 32-character hexadecimal hash
- • Historical Importance: Ancestor of MD5and SHA families
- • NTLM Usage: Still used in Windows NTLM authentication
📊 Where MD4 is Still Used
- • NTLM Authentication: Windows domain authentication
- • ED2K Links: eDonkey2000 file hashing
- • Legacy Systems: Older systems requiring MD4 compatibility
- • Research: Studying hash function evolution
⚠️ Security WARNING
MD4 is COMPLETELY BROKEN cryptographically. Full collisions can be found in milliseconds. NEVER use MD4 for security, password hashing, or digital signatures. It is included here for compatibility with legacy systems only. Use SHA-256 or SHA-512 for any security purpose.
🔄 MD4 vs Related Algorithms
MD4
128-bit, 3 rounds
Broken - collisions in ms
MD5
128-bit, 4 rounds
Also broken, but slower to attack
SHA-256
256-bit output
Secure, recommended for new systems
❓ Frequently Asked Questions
Why does MD4 still exist if it's broken?
MD4 is still used in Microsoft's NTLM authentication and eDonkey file sharing. Legacy compatibility keeps it alive, though all new systems should avoid it.
What's the difference between MD4 and MD5?
MD5 added a fourth round of operations and modified the step functions to fix weaknesses in MD4. Both produce 128-bit hashes, but MD5 is more collision-resistant (though also broken).
Is my data sent to a server?
The hash is computed on our server via a secure AJAX request, but your data is never stored and the connection is encrypted.